Briefly about Ano Oni Kyōshi Ga Boku No Ane Ni Narundesuka? manga:Despite being the younger brother, he is an honor student who is very popular amongst his peers. One day, he learns that his father remarried and gained an older sister. Much to his confusion, his new sister is actually Shina, a woman who teaches physical education at the school he goes to! As if things aren\'t bad enough, the two now have to live together! Will these siblings be able to get along?